Polyphenylene ether-polyamide blends

ABSTRACT

Novel polyphenylene ether-polyamide compositions having improved compatibility, elongation and impact properties as well as improved processability are prepared comprising a polyphenylene ether, a polyamide and a property improving amount of an acyl modified polyphenylene ether compatibilization agent. These compositions may further comprise alkenyl aromatic polymer or a rubbery polymer.

The present invention relates to polyphenylene ether-polyamide blendshaving improved chemical resistance, processability, elongationproperties and impact strength. More specifically, it relates to a resincomposition which comprises (a) a polyphenylene ether resin, (b) apolyamide resin and (c) a compatibilizing amount of a polyphenyleneether resin modified with an acyl functional compound. Thesecompositions may also contain additional impact modifiers and/orreinforcing agents for added strength.

The polyphenylene ether resins are characterized by a unique combinationof chemical, physical and electrical properties over a temperature rangeof more than 650° F., extending from a brittle point of about -275° F.to a heat distortion temperature of about 375° F. This combination ofproperties renders the polyphenylene ethers suitable for a broad rangeof applications. However, in spite of the aforementioned beneficialproperties, the usefulness of the polyphenylene ether resins is limitedin some applications as a consequence of processability, impactresistance and chemical resistance.

Finholz (U.S. Pat. No. 3,379,792) discloses polymer blends wherein theprocessability of polyphenylene ether resins may be improved by blendingwith from 0.1 to 25% by weight of a polyamide. However, the advantagesof the Finholt invention are limited by the fact that when theconcentration of the polyamide exceeds 20% by weight, appreciable lossesin other physical properties result. Specifically, there is no, or atbest poor, compatibility between the polyphenylene ether and thepolyamide such that phase separation of the resins occurs on molding orthe molded article is inferior in mechanical properties.

Ueno et al. (U.S. Pat. No. 4,315,086) discloses polyphenylene etherblends having improved chemical resistance without a loss of othermechanical properties by blending therewith a polyamide and a specificcompound selected from the group consisting essentially of (A) liquiddiene polymers, (B) epoxy compounds and (C) compounds having in themolecule both of (i) an ethylenic carbon-carbon double bond orcarbon-carbon triple bond and (ii) a carboxylic acid, acid anhydride,acid amide, imide, carboxylic acid ester, amino or hydroxy group.

Finally, Kasahara et al. (EP No. 46040) discloses the use of a copolymercomprising units of a vinyl aromatic compound and either an alpha,beta-unsaturated dicarboxylic acid anhydride or an imide compoundthereof as a modifier to an impact resistant polyphenyleneether-polyamide blend for improved heat resistance and oil resistance.

Applicants have now discovered novel polyphenylene ether-polyamideblends having improved impact strength, elongation, chemical resistance,processability and/or heat resistance as well as reduced waterabsorption as compared to unmodified polyphenylene ether-polyamidecompositions.

Specifically, applicants have discovered novel resin compositions havingthe aforementioned properties comprising a polyphenylene ether, apolyamide and a property improving amount of the effective acylfunctional compatibilizer described in detail below.

It has been discovered, for example, that polyphenylene ether reactedwith trimellitic anhydride acid chloride (TAAC) and the reaction productPPE-TAAC functions very effectively as a compatibilizer forpolyphenylene ether-polyamide blends. With proper impact modification,the resultant blends exhibit very attractive physical properties such ashigh HDT, good impact strength and mechanical properties, low shrinkage,and outstanding chemical resistance and hydrolytic stability for manyend-use applications.

It also has been discovered that PPE-TAAC is superior to maleicanhydride as a compatibilizer for polyphenylene ether-polyamide blendsin many respects.

For example, PPE-TAAC compatibilizer offers better color stability.Significant discoloration of PPE/Nylon 6.6/maleic anhydride blends wasobserved after extrusion. Such discoloration was not evident inPPE/PPE-TAAC/Nylon 6.6 blends.

PPE-TAAC compatibilizer offers improved dimensional stability. Highermold shrinkage was observed in PPE/Nylon 6.6/maleic anhydride blends incomparison with PPE/PPE-TAAC/Nylon 6.6 blends having comparable physicalproperties.

PPE-TAAC compatibilizer offers higher matrix ductility. Impact modifiedPPE/Nylon 6.6/maleic anhydride blends exhibited significantly lower Izodimpact strength and less ductile failure behavior in a falling dart testthan corresponding PPE/PPE-TAAC/Nylon 6.6 blends. The mode of ductilefailure can be an extremely important consideration when choosing athermoplastic for various end-use applications.

PPE-TAAC compatibilizer provides better phase dispersion and interfacialadhesion. PPE/Nylon 6.6/maleic anhydride blends were judged frommorphology and solubility test results to have much inferior phasedispersion and interfacial adhesion compared to PPE/PPE-TAAC/Nylon 6.6blends.

SUMMARY OF THE INVENTION

There is provided a thermoplastic composition comprising:

(a) a polyphenylene ether resin;

(b) a polyamide resin; and

(c) compounds which contain in the molecule both (i) at least one grouphaving the formula ##STR1## where X is F, Cl, Br, I, OH, ##STR2## whereR is H or an alkyl or aryl radical and (ii) at least one carboxylicacid, acid anhydride, acid amide, imido, carboxylic acid ester, amino orhydroxyl group; wherein groups (i) and (ii) are covalently bonded;wherein the molecule containing groups (i) and (ii) is covalently bondedto a polyhenylene ether molecule; and wherein compound (c) is present inan amount sufficient to effect compatibilization of resinous components(a) and (b).

The intended scope of the invention encompasses physical admixtures ofthe required constituents by conventional means, chemical reactionproducts of the various components, and blends and reaction products ofvarious combinations of the requisite materials which may be latercombined into a compatible product. The expressions "polyphenyleneether-polyamide blend" and "PPE-PA" are intended to encompass each ofthese possibilities.

The invention encompasses compatible blends of polyphenylene ether andpolyamide in any proportion. Typically, however, the polyphenylene ether(a) will be present in an amount of 5 to 95 weight percent and thepolyamide (b) will be present at 95 to 5 weight percent, based upon theweights of (a) and (b) together.

A preferred composition might comprise 25 to 75 weight percentpolyphenylene ether and 75 to 25 weight percent polyamide.

Compatibilizing compound (c) will be present in an amount at leastsufficient to effect compatibility of resinous components (a) and (b).The expression "compatibility" is also intended to encompass adequatedispersion of the two resins (a) and (b) in a manner which providesuseful thermoplastic compositions, as well as useful non-delaminatningproducts.

Typically, at least about 1 part by weight of compatibilizing component(c) will be necessary per 100 parts of resinous components (a) and (b).Preferred formulations may contain, approximately 10 to 30 parts byweight of compatibilizing component (c) per 100 parts (a) and (b).

Thus a typical embodiment of the present invention comprises anadmixture of polyphenylene ether, polyamide and a compatibilizing agentsuch as polyphenylene ether reacted with trimellitic anhydride acidchloride (PPE-TAAC).

Alternatively, the compatibilizing agent can first be precompounded orprereacted with either of the two resinous materials (a) or (b).Furthermore, the polyphenylene ether-trimellitic anhydride acid chloridecombination reaction product (PPE-TAAC) can replace all or some of thepolyphenylene ether in a polyphenylene ether polyamide product.

DESCRIPTION OF THE INVENTION

Preferred polyphenylene ethers are homopolymers or copolymers havingunits with the repeating structural formula: ##STR3## wherein the oxygenether atom of one unit is connected to the benzene nucleus of the nextjoining unit, and n is a positive integer of at least 50, and each Q is,independently, a monovalent substituent selected from a group consistingof hydrogen, halogen, hydrocarbon and hydrocarbonoxy groups free of atertiary alpha-carbon atom, and halohydrocarbon and halohydrocarbonoxygroups free of a tertiary alpha-carbon and having at least 2 carbonatoms between the halogen atom and the phenyl nucleus.

A particularly preferred polyphenylene ether ispoly(2,6-dimethyl-1,4-phenylene)ether.

Compatible compositions of the present invention are intended to includeany of the well known polyamides or nylons such as polyamide 6;polyamide 6/6; polyamide 4/6; polyamide 12; and polyamide 6/10, andcombinations of these where appropriate. Polyamide 6/6 or polyamide 6 ispreferred.

Optionally, the compositions of the present invention may furthercomprise polymeric impact modifiers, inorganic reinforcing additives orother polymers including alkenyl aromatic polymers such as the styrenicpolymers.

The improved polyphenylene ether-polyamide compositions of the presentinvention may be made by melt blending the above-mentioned ingredients.Alternatively, it may be preferred to achieve optimum propertyimprovements to precompound the property improving compatibilizingagent, together with either one of the polymer resins.

Although the exact physical configuration of the compositions of thepresent invention is not known, it is generally believed that thecompositions comprise a dispersion of one polymer in the other. A likelyconfiguration is wherein the polyphenylene ether is dispersed in apolyamide matrix, however, the inverse may also be possible,particularly where the polyamide is present in only a minor amount.Applicants also contemplate that they may be present in the productsproduced hereby some graft polyphenylene ether-polyamide products. Thus,all such dispersions as well as graft, partially grafted and non-graftedproducts are within the full intended scope of the invention.

The polyphenylene ethers suitable for use in the practice of the presentinvention are well known in the art and may be prepared by any of anumber of catalytic and non-catalytic processes from correspondingphenols or reactive derivatives thereof. Examples of polyphenyleneethers and methods for their production are disclosed in U.S. Pat. Nos.3,306,874; 3,306,875; 3,257,357; 3,257,358; 3,337,501 and 3,787,361, allincorporated herein by reference. For brevity, the term "polyphenyleneether" as used throughout this specification and the appended claimswill include not only unsubstituted polyphenylene ether (made fromphenol) but also polyphenylene ethers with various substituents. Theterm also includes polyphenylene ether copolymers; as well as graft andblock copolymers of alkenyl aromatic compounds, especially vinylaromatic compounds, as disclosed below, and a polyphenylene ether.

Suitable phenol compounds for the preparation of the polyphenyleneethers may be represented by the general formula: ##STR4## wherein eachQ is a monovalent substituent individually selected from the groupconsisting of hydrogen, halogen, aliphatic and aromatic hydrocarbon andhydrocarbonoxy radicals free of a tertiary alpha-carbon atom andhalohydrocarbon and halohydrocarbonoxy radicals free of a tertiaryalpha-carbon atom and having at least two carbon atoms between thehalogen atom and the phenyl nucleus, and wherein at least one Q ishydrogen.

As specific examples of the phenol compound represented by the aboveformula, there may be given phenol; o-, m- and p-cresols; 2,6, 2,5, 2,4and 3,5 dimethylphenols; 2-methyl-6-phenyl-phenol; 2,6-diphenylphenol;2,6-diethylphenol; 2-methy-6-ethyl-phenol; and 2,3,5-, 2,3,6- and2,4,6-trimethylphenols. Two or more phenol compounds may be used incombination should copolymers be desired. Additionally, copolyphenyleneethers may also be prepared from a phenol compound of the above generalformula with a phenol compound not represented by the above generalformula including, for example, a dihydric phenol such as bisphenol-A,tetrabromobisphenol-A, resorcinol or hydroquinone.

Illustrative of suitable polyphenylene ethers there may be given forexample,

poly(2,6 dimethyl-1,4-phenylene)ether;

poly(2-methyl-1,4-phenylene)ether,

poly(3-methyl-1,4-phenylene)ether;

poly(2,6-diethyl-1,4-phenylene)ether;

poly(2-methyl-6-allyl-1,4-phenylene)ether;

poly(2,6-dichloromethyl-1,4-phenylene)ether;

poly2,3,6-trimethyl-1,4-phenylene)ether;

poly(2,3,5,6-tetramethylphenylene)ether;poly(2,6-dichloro-1,4-phenylene)ether;

poly(2,6-diphenyl-1,4-phenylene)ether;

poly(2,5-dimethyl-1,4-phenylene)ether and the like.

Further, as mentioned above, copolymers of the phenol compounds may alsobe used.

Preferred polyphenylene ethers will have the formula: ##STR5## where Qis as defined above and n is at least 50, preferably from about 50 toabout 200. Examples of polyphenylene ethers corresponding to the aboveformula can be found in the above referenced patents and include, amongothers:

poly(2,6-dilauryl-1,4-phenylene)ether;

poly(2,6-diphenyl-1,4-phenylene)-ether;

poly(2,6-dimethyoxy-1,4-phenylene)ether;

poly(2,6-diethoxy-1,4-phenylene)ether;

poly(2-methoxy-6-ethyoxy-phenylene)ether;

poly(2-ethyl-6-tearyloxy-1,4-phenylene)ether;

poly(2,6-dichloro-1,4-phenylene)ether;

poly(2-methyl-6-phenyl-1,4-phenylene)ether

poly(2,6-dibenzyl-1,4-phenylene)ether;

poly(2-ethoxy-1,4-phenylene)ether;

poly(2-chloro-1,4-phenylene)ether;

poly(2,6-dibromo-1,4-phenylene)-ether; and the like.

For the purpose of the present invention, an especially preferred familyof polyphenylene ethers include those having a C₁ to C₄ alkylsubstitution in the two positions ortho to the oxygen ether atom.Illustrative members of this class are:

poly(2,6-dimethyl-1,4-phenylene)ether:

poly(2,6-diethyl-1,4-phenylene)ether;

poly(2-methyl-6-ethyl-1,4-phenylene)ether;

poly(2,6-dipropyl-1,4-phenylene)ether;

poly(2-ethyl-6-propyl-1,4-phenylene)ether; and the like;

most preferably poly(2,6-dimethyl-1,4-phenylene)ether.

One method for the production of the above polyphenylene ethers is bythe oxidation of a phenol compound by oxygen or an oxygen-containing gasin the presence of a catalyst for oxidative coupling. There is noparticular limitation as to the choice of catalysts and any catalystsfor oxidation polymerization can be employed. As typical examples of thecatalyst, there may be given a catalyst comprising a cuprous salt and atertiary amine and/or secondary amine, such as cuprouschloride-trimethylamine and dibutylamine, cuprous acetate-triethylamineor cuprous chloride-pyridine; a catalyst comprising a cupric salt, atertiary amine, and an alkali metal hydroxide, such a cupricchloride-pyridine-potassium hydroxide; a catalyst comprising a manganesesalt and a primary amine, such a manganese chloride-ethanolamine ormanganese acetate-ethylenediamine; a catalyst comprising a manganesesalt and an alcoholate or phenolate, such as manganese chloride-sodiummethlate or manganese chloride-sodium phenolate; and a catalystcomprising a cobalt salt and a tertiary amine.

Polyamides suitable for the preparation of the compositions of thepresent invention may be obtained by polymerizing amonoamino-monocarboxylic acid or a lactam thereof having at least 2carbon atoms between the amino and carboxylic acid group; or bypolymerizing substantially equimolar proportions of a diamine whichcontains at least 2 carbon atoms between the amino groups anddicarboxylic acid; or by polymerizing a monoaminocarboxylic acid or alactam thereof as defined above together with substantiallyequimolecular proportions of a diamine and a dicarboxylic acid. Thedicarboxylic acid may be used in the form of a functional derivativethereof, for example an ester or acid chloride.

The term "substantially equimolecular" proportions (of the diamine andof the dicarboxylic acid) is intended to encompass both strictequimolecular proportions and slight departures therefrom which areinvolved in conventional techniques for stabilizing the viscosity of theresultant polyamides.

Examples of the aforementioned monoamino-monocarboxylic acids or lactamsthereof which are useful in preparing the polyamides include thosecompounds containing from 2 to 16 carbon atoms between the amino andcarboxylic acid groups, said carbon atoms forming a ring with the--CO--NH-- group in the case of a lactam. As particular examples ofaminocarboxylic acids and lactams there may be mentionedgama-aminocaproic acid, butyrolactam, pivalolactam, caprolactam,capryllactam, enantholactam, undecanolactam, dodcanolactam and 3- and4-aminobenzoic acids.

Examples of diamines suitable for preparing the polyamides includediamines of the general formula

    H.sub.2 N(CH.sub.2).sub.n NH.sub.2

wherein n is an integer of from 2 to 16, such as trimethylenediamine,tetramethylenediamine, pentamethylenediamine, octamethylenediamine andespecially hexamethylenediamine.

The dicarboxylic acids may be aromatic, for example isophthalic andterephthalic acids. Preferred dicarboxylic acids are of the formula

    HOOC--Y--COOH

wherein Y represents a divalent aliphatic group containing at least 2carbon atoms, and examples of such acids are sebacic acid,octadecanedoic acid, suberic acid, glutaric acid, pimelic acid andadipic acid.

Typical examples of the polyamides or nylons, as these are often called,include for example polyamides 6, 6/6, 11, 12, 6/3, 6/4, 6/10 and 6/12as well as polyamides resulting from terephthalic acid and trimethylhexamethylene diamide, polyamides resulting from solipic acid and metaxylylenediamines, polyamides resulting from adipic acid, azelaic acidand 2,2-bis-(p-aminocyclohexyl)propane and polyamides resulting fromterephthalic acid and 4,4'-diamino-dicyclohexylmethane. Preferredpolyamides are the polyamides 6, 6/6, 4/6, 11 and 12, most preferablypolyamide 6/6 or polyamide 6.

The blending ratio of polyphenylene ether to polyamide is 5 to 95% byweight preferably 25 to 75% by weight of the former to 95 to 5% byweight, preferably 75 to 25% by weight of the latter. When the polyamideis less than 5 weight percent, its effect to improve solvent resistanceis small, and when it exceeds 95 weight percent, thermal properties suchas heat distortion temperature tend to become poor.

Compatibility between the polyphenylene ether resin and the polyamideresin is believed to be achieved when the compatibilizing agent ischemically or physically associated with both resins.

For example, a linear polyphenylene ether having an end group of formulaI: ##STR6## may be reacted in the presence of heat and solvent with acompound such as trimellitic anhydride acid chloride of formula II:##STR7## to provide a PPE-TAAC compatibilizing agent of formula IIIwhich may be appropriately purified as by precipitation in methanol oracetone: ##STR8##

This exemplary PPE-TAAC compatibilizing agent can partially or totallyreplace the PPE in a PPE/polyamide blend. A preferred thermoplasticblend of the present invention would comprise PPE/PPE-TAAC/polyamide, ormerely PPE-TAAC/polyamide.

The anhydride portion of this compatibilization agent is believed to beprimarily responsible for the chemical or physical association of theagent with the polyamide resin.

Of course it is contemplated that the compatibilization agent can begeneralized to encompass a number of other effective agents which wouldact similarly to the preferred PPE-TAAC agents discussed above.

For example, the portion of the compatibilizing molecule associated orbonded to the PPE resin chain can be generalized as an acyl-functionalgroup depicted by formula IV: ##STR9## where x is F, CL, Br, I, OH,##STR10## etc. and where R is H or an aliphatic or aromatic radicalhaving less than about 10 carbon atoms. The moiety of formula IV iscovalently bonded to a group which is primarily responsible forassociating or bonding with the polyamide portion of the thermoplasticcomposition. In the preferred embodiment discussed above, this group isan anhydride group as shown in formula V ##STR11## where R₁, R₂, R₃, andR₄ are each, independently, H or an aliphatic or aromatic radical(having, preferably, less than about 10 carbon atoms).

Examples of suitable materials falling with the scope of the inventioninclude but are not limited to the following compatiblizer precursors:##STR12##

Of course, compatibilizer precursors effective in this invention are notlimited to the preferred anhydrides mentioned above. It is well knownthat polyamides will react or associate with a very large number ofmolecules containing groups chosen from among carboxylic acid (includingmono- and poly-acids), acid anhydride, acid amide, imido carboxylic acidester, amino or hydroxyl groups.

Thus it is contemplated that the acid chloride of terephthalic acid canalso be utilized. ##STR13##

The amount of the compatibilizing precursor to be used is that amountwhich manifests property improvement, especially improved compatibilityas well as improved processability, impact strength and/or elongation,in the polyphenylene ether-polyamide compositions. In general, theamount of compatibilizer precursor used to react with polyphenyleneether will be up to about 6%, preferably from about 0.05 to about 4% byweight based on the polyphenylene ether. The specific amount of thecompatibilizer to be used to achieve optimum results for a givencomposition is dependent, in part, on the specific compatibilizerprecursor, the specific polyphenylene ether to be reacted, the specificpolyphenylene ether and polyamide to be compatibilized and the weightratio of said polymers and the processing conditions. A variety ofsuitable combinations can be achieved without undue experimentation.

In addition to the improved processability, impact strength andelongation, many of the compositions prepared in accordance with thepresent invention manifest improvements in other physical properties andcharacteristics including for example, reduced water absorption.

The above-mentioned property improving compatibilizer compound may beused alone or in combination with a primary or secondary amine. Thepresence of the amine may enhance the improvement of certain physicalproperties when used in combination with various compatibilizers.Suitable amines include those primary and secndary amines having from 1to about 20, preferably from 1 to about 10 carbon atoms. Examples ofsaid suitable amines are, methyl ethylamine, diethylamine, butylamine,dibutylamine, analine, n-octadecylamine and the like. The amount of theprimary or secondary amine to be used is generally up to about 3% byweight, preferably up to about 1% by weight.

In the practice of the present invention, it may be further desirable toadd rubbery high-molecular weight polymers to further improve thephysical properties such as impact strength, and processability. Therubbery high-molecular weight materials include natural and syntheticpolymeric materials showing elasticity at room temperature. Morespecifically, the rubbery high molecular weight materials includenatural rubber, thermoplastic elastomers as well as homopolymers andcopolymers, including random, block and graft copolymers derived fromvarious suitable monomers known to those skilled in the art includingbutadiene, possibly in combination with vinyl aromatic compounds,especially styrene. As specific examples of the rubbery high-molecularweight materials, there may be given, for example, natural rubber,butadiene polymers, styrene copolymers, butadiene/styrene copolymers,isoprene polymers, chlorobutadiene polymers, butadiene/acrylonitrilecopolymers, isobutylene polymers, isobutylene/butadiene copolymers,isobutylene/isoprene copolymers, acrylic ester polymers, ethylenepropylene copolymers, ethylene/propylene/diene copolymers, thiokolrubber, polysulfide rubber, polyurethane rubber, polyether rubber (e.g.polypropylene oxide) and epichlorohydric rubber.

A preferred class of rubber materials are copolymers, including random,block and graft copolymers of vinyl aromatic compounds an conjugateddienes. Exemplary of these materials there may be given hydrogenated ornon-hydrogenated block copolymers of the A-B-A and A-B type wherein A ispolystyrene and B is an elastomeric diene, e.g. polybutadiene, radialteleblock copolymer of styrene and a conjugated diene, acrylic resinmodified styrene-butadiene resins and the like; and graft copolymersobtained by graft-copolymerization of a monomer or monomer mixcontaining a styrenic compound as the main component to a rubber-likepolymer. The rubber-like polymer used in the graft copolymer as alreadydescribed herein including polybutadiene, styrene-butadiene copolymer,acrylonitrile-butadiene copolymer, ethylene-propylene copolymer,polyacrylate and the like. The styrenic compounds include styrene,methylstyrene, dimethylstyrene, isopropylstyrene, alpha-methylstyrene,ethylvinyltoluene and the like. The monomer which may be used togetherwith the styrenic compound includes, for example, acrylate,methyacrylate, acrylonitrile, methyacrylonitrile, methyacrylic acid,acrylic acid and the like.

Finally, additional thermoplastic elastomers suitable for use as therubbery material include thermoplastic polyester elastomers,thermoplastic polyether-ester elastomers, ethylenic ionomer resins andthe like.

The amount of the rubbery polymer used will be up to about 100 parts byweight, preferably from about 5 to about 50 parts by weight based on 100parts by weight of a mixture of polyphenylene ether and polyamide.However, when the amount is less than 2 parts by weight, the effect ofthe rubbery polymer to improve impact resistance is poor. When theamount is more than 100 parts by weight, the impact resistance is muchimproved, however, some loss of other physical properties may result. Inthe interest of balancing impact resistance and other physicalproperties, it is preferred to use less than 100 parts by weight of therubber polymer.

The compositions of the present invention may also comprise similaramounts, as referred to above, of alkenyl aromatic compounds. Thesealkenyl aromatic compounds may or may not be partially or whollycopolymerized with and/or grafted to the polyphenylene ether.Especially, suitable are the styrene resins described in for exampleU.S. Pat. No. 3,383,435, incorporated herein by reference. In general,the styrene resins will have at least 25% by weight of the polymer unitsderived from a vinyl aromatic compound of the formula: ##STR14## whereinR^(V) is hydrogen, (lower) alkyl or halogen, Z is vinyl, halogen or(lower) alkyl, and p is 0 or an integer of from 1 to the number ofreplaceable hydrogen atoms on the benzene nucleus. Herein, the term"(lower) alkyl" is intended to mean alkyl of from 1 to 6 carbon atoms.

The term "styrene resins" as used broadly throughout this disclosure andthe appended claims includes, by way of example, homopolymers such aspolystyrene, polychlorostyrene and polybromostyrene, as well aspolystyrenes, including high impact polystyrenes, which have beenmodifed by a natural or synthetic rubber, e.g. polybutadiene,polyisoprene, butyl rubber, ethylene-propylene diene copolymers-(EPDMrubber), ethylene-propylene copolymers, natural rubbers, polysulfiderubbers, polyurethane rubbers, styrene-butadiene rubbers (SBR), and thelike: styrene containing copolymers such as styrene-acrylonitrilecopolymers (SAN), styrene-butadiene copolymers, styrene-bromostyrenecopolymers especially styrene-dibromostyrene copolymers,styrene-acrylonitrile-butadiene terpolymers (ABS),poly-alpha-methylstyrene, copolymers of ethylvinyl benzene anddivinylbenzene and the like.

Finally, in addition to the foregoing, the resin compositions of thepresent invention may further comprise other reinforcing additives,including glass fibers, carbon fibers, mineral fillers and the like aswell as various flame retardants, colorants, stabilizers and the likeknown to those skilled in the art.

The method for producing the resin compositions of the present inventionis not particularly limited, and the conventional methods aresatisfactorily employed. Generally, however, melt blending methods aredesirable. The time and temperature required for melt-blending are notparticularly limited, and they can properly be determined according tothe composition of the material. The temperature varies somewhat withthe blending ratio of the polyphenylene ether to polyamide, but it isgenerally within a range of 270° to 350° C. A prolonged time and/or ahigh shear rate is desirable for mixing, but the deterioration of theresin composition advances. Consequently, the time needs to bedetermined taking into account these points.

Any of the melt-blending methods may be used, if it can handle a moltenviscous mass. The method may be applied in either a batchwise form or acontinuous form. Specifically, extruders, Banbury ixers, rollers,kneaders, and the like may be exemplified.

All ingredients may directly be added to the processing system or onepolymer. With respect to the other ingredients of the composition, allingredients may be added directly to the processing system or certainadditives may be precompounded with each other or either polymer priorto blending with the other polymer. For example, the polyphenylene ethermay be precompounded with the rubber polymer and/or the compatibilizerand subsequently compounded with the polyamide.

All the aforementioned patents or applications are hereby incorporatedby reference. The following examples are given to illustrate theinvention without limitation.

EXAMPLE 1 Synthesis of PPE-TAAC

Various polyphenylene ether-trimellitic anhydride acid chloride reactionproducts were prepared. Either 100 parts of a 30% by weight solution ofpoly(2,6 dimethyl-1,4-phenylene)ether (in toluene obtained directly fromthe polymerization of 2,6-xylenol in toluene after removal of coppercatalyst) was utilized ("PRE CON" PPE), or 100 parts of an "isolatedPPE" obtained by methanol precipitation and dissolved in 500 partstoluene was used. One hundred parts of PPE was reacted with between 1.7to 2.3 parts of trimellitic anhydride acid chloride (TAAC), and between4.1 to 5.8 parts of dimethyl-n-butylamine (DMBA) was utilized as an acidacceptor. The reactions were carried out at 95° C. for between 0.5 to3.0 hours.

The TAAC was obtained from Aldrich Chemical at a purity of 99%,molecular weight 210.57 g/mole, and melting point of 66° to 68° C.

The reaction products were purified by precipitation in methanol andthereafter dried overnight in a vacuum oven at 60° to 80° C.

The formation of PPE-TAAC was verified by infrared analysis whichindicated a reduction of a known PPE hydroxyl peak at 2650 to 2900 nmand the appearance of a carbonyl absorption peak appeared at 1730-1740cm⁻¹.

Table 1 details conditions for reaction of PPE and TAAC.

                                      TABLE 1                                     __________________________________________________________________________    Conditions For Reaction of PPE With TAAC                                      WT % PPE      WEIGHT % PPE                                                                            g TAAC/                                                                             g DMBA/                                                                             TIME AT                                   SAMPLE DESCRIPTION                                                                          in TOLUENE                                                                              100 g PPE                                                                           100 g PPE                                                                           95° C. hrs.                        __________________________________________________________________________    Methanol Ppt. PPE                                                                           20        2.1   4.1   3                                         Methanol Ppt. PPE                                                                           20        2.3   4.1   1.5                                       Pre Con PPE   30        2.3   5.8   1.5                                       Pre Con PPE   30        2.3   5.8   0.5                                       Pre Con PPE   30        1.7   5.8   0.5                                       __________________________________________________________________________

EXAMPLES 2-3 Compatibilization of Polyphenylene Ether-Polyamide Blends

PPE-TAAC prepared as described above was evaluated as a compatibilizerfor PPE-polyamide blends and its performance was compared with a knowncompatibilizing agent, maleic anhydride, in a variety of blends.

The maleic anhydride was obtained from Aldrich at 99% purity, molecularweight 98.06 g/mole, and melting point of 54°-56° C. The polyamide was ageneral purpose nylon 6.6, Zytel-101, obtained from DuPont. The PPE waspoly(2,6 dimethyl-1.4-phenylene)ether resin manufactured by GeneralElectric Company.

Samples were extruded using a 28 mm Werner-Pleiderer twin screw extruderat 65% torque and full RPM with a heat profile of 350°, 450°, 500°,550°, 550°, 550°, 550° F.

Samples were molded on a 3 oz. Newbury injection molding machine at550°/150° C., 15/40 sec cycle, 100 RPM and 100 PSI back pressure.

Specimens used for HDT, Izod impact, and tensile tests were 1/8 inch×1/2inch×21/2 inch minibars. Dynatup (FDI) test specimens were 1/8 inch×4inch round discs.

Table 2 demonstrates improvements in compositions of the presentinvention in comparison with non-compatibilized blends or thosecompatibilized with maleic anhydride.

                  TABLE 2                                                         ______________________________________                                                        SAMPLE                                                                        A*   B*     C*     2    3                                     ______________________________________                                                  PPE             49   49   49   24.5 --                                        PPE-TAAC        --   --   --   24.5 49                                        NYLON 6,6       41   41   41   41   41                                        MALEIC          --    .50 1.0  --   --                                        ANHYDRIDE                                                                     KG-1651**       10   10   10   10   10                                        HDT ('F) @ 264 psi                                                                            367  368  380  357  360                                       IZOD (ft.lb/in)  .10 3.5  3.3  5.9  4.6                                       DYNATUP (in.lb)  2   363  334  387  312                                       TENSILE YIELD   7.3  8.6  8.5  9.0  9.1                                       (kpsi)                                                                        TENSILE STRENGTH                                                                              7.1  7.9  8.0  8.3  8.0                                       (kpsi)                                                                        TENSILE         11   123  124  140  89                                        ELONGATION %                                                                  SHRINK (in/in × 10.sup.-3)                                                              14.4 10.6 9.8  10.2 9.3                                       T.Y. ORIGINAL   7.3  8.6  8.5  9.0  9.1                                       (NO AGEING)                                                                   0% STRAIN       96   101  100  99   100                                       % ORIGINAL T.Y.                                                               1/2% STRAIN     90   101  102  98   101                                       % ORIGINAL T.Y.                                                     ***       1% STRAIN       79   99   99   99   99                                        % ORIGINAL T.Y.                                                               2% STRAIN       44   57   87   97   80                                        % ORIGINAL T.Y.                                                     ______________________________________                                         *Comparative                                                                  **Kraton Rubber, Shell Chemical Co. The Kraton D series is a polymer of       the styreneethylene/butylene type (SEB-S).                                    ***Chemical resistance data. It is judged by the retention of tensile         yield strength @ 185° F., 3 days, in Ford brake fluid as a testing     environment.                                                             

EXAMPLES 4-7

The compositions described in Table 3 demonstrate the significantimprovements in physical properties exhibited by blends of the presentinvention. Especially notable are improvements in impact strength.

                  TABLE 3                                                         ______________________________________                                        SAMPLE         4      5      D*   E*   6    7                                 ______________________________________                                        PPO            24.5   24.5   50   25   25   12.5                              PPO-TAAC (isolated)                                                                          24.5   --     --   --   --   --                                PPO-TAAC (body feed)                                                                         --     24.5   --   --   25   12.5                              NYLON 6,6      41     41     50   75   50   75                                KG-1651        10     10     10   10   10   10                                HDT ('F) @ 264 psi                                                                           361    370    374  373  372  371                               IZOD (ft. lb/in)                                                                             5.4    7.2    0.3  0.9  4.9  3.7                               DYNATUP (in.lb)                                                                              366    341    13   141  420  427                               TENSILE YIELD  8.9    9.1    8.3  8.7  9.2  9.1                               (kpsi)                                                                        TENSILE STRENGTH                                                                             8.0    8.0    8.1  8.1  8.1  7.9                               (kpsi)                                                                        TENSILE        98     80     16   56   72   86                                ELONGATION (%)                                                                SHRINK (in/in × 10.sup.-3)                                                             8.0    7.9    9.5  9.8  7.7  7.9                               FM             --     --     318  325  322  337                               FS (kpsi)      --     --     12.7 12.8 13.1 13.7                              DELAMINATION   N      N      N    N    N    N                                 T.Y. ORIGINAL  8.9    9.1    8.3  8.7  9.2  9.1                               (NO AGEING)                                                                   ______________________________________                                         *Comparative Examples                                                    

EXAMPLES 8-12

The solubility of PPE-Polyamide blends in formic acid and toluene wereevaluated. Table 4 demonstrates that compositions of the presentinvention exhibit considerably more reaction of PPE with Nylon 6,6 whenPPE-TAAC is used as a compatibilizer than when maleic annydride is usedas a compatibilizer as evidenced by the decreasing solubility of theformic acid insoluble fraction of the blends in toluene.

                                      TABLE 4                                     __________________________________________________________________________    SAMPLE       F* G*  H* I* J* 8  9  10 11 12                                   __________________________________________________________________________    PPE          50 50  50 50 50 47.5                                                                             45 40 25 --                                   PPE-TAAC     -- --  -- -- --  2.5                                                                              5 10 25 50                                   Maleic Anhydride                                                                           --   .25                                                                              .5                                                                               1.0                                                                              2.0                                                NYLON 6,6    50 50  50 50 50 50 50 50 50 50                                   % Soluble in 90% Formic                                                                    50.5                                                                             50.3                                                                              50.4                                                                             48.4                                                                             50.4                                                                             50.3                                                                             50.7                                                                             50.6                                                                             49.1                                                                             48.6                                 Acid (25 C)                                                                   % Soluble in Toluene                                                                       93.1                                                                             83.8                                                                              83.7                                                                             87.2                                                                             88.3                                                                             88.1                                                                             81.5                                                                             77.8                                                                             59.7                                                                             25.3                                 (of formic acid insoluble                                                     material 25 C)                                                                __________________________________________________________________________     *Comparative Examples                                                    

EXAMPLES 13-17

Table 5 demonstrates the effect of various levels of compatibilizers inPPE-Polyamide blends. Compatible PPE-Polyamide blends of the presentinvention can be provided with a range of suitable properties asrequired for varied applications.

                                      TABLE 5                                     __________________________________________________________________________    Sample          K* L* M* N* O* 13  14  15 16 17 P* Q*  R*                     __________________________________________________________________________    PPE             50 50  50                                                                               50                                                                              50 47.5                                                                              45  40 25 -- 100                                                                              --  --                     PPE-TAAC        -- -- -- -- --  2.5                                                                               5  10 25 50 -- --  --                     NYLON 6,6       50 50  50                                                                               50                                                                              50  50 50  50 50 50 -- 100 100                    MALEIC ANHYDRIDE                                                                              --  .25                                                                              .50                                                                             1.0                                                                              2.0                                                                              --  --  -- -- -- -- --  --                     HDT('F) @ 264 psi                                                                             416                                                                              382                                                                              386                                                                              381                                                                              384                                                                              377 392 387                                                                              373                                                                              376                                                                              384                                                                              388 394                    IZOD (ft. lb/in)                                                                               .16                                                                              .24                                                                              .16                                                                              .24                                                                              .44                                                                               .12                                                                               .16                                                                              .12                                                                              .32                                                                              .40                                                                              .80                                                                               .36                                                                             1.04                   DYNATUP (in.lb)  5 16  35                                                                               33                                                                              20  7   9  10 15 24 21 17  314                    TENSILE YIELD (kpsi)                                                                          10.1                                                                             11.3                                                                             10.8                                                                             11.4                                                                             11.5                                                                             10.7                                                                              11.4                                                                              11.5                                                                             11.3                                                                             11.3                                                                             11.8                                                                             12.5                                                                              12.6                   TENSILE STRENGTH (kpsi)                                                                       9.2                                                                              6.9                                                                              7.4                                                                              6.9                                                                              7.3                                                                              10.6                                                                              11.3                                                                              7.0                                                                              6.7                                                                              6.9                                                                              9.8                                                                               4.8                                                                               8.4                   TENSILE ELONGATION (%)                                                                        11 52 142                                                                              105                                                                              73  17 19  49 66 73 76 63  200                    SHRINK (in/in × 10.sup.-3)                                                              9.2                                                                              8.1                                                                              8.2                                                                              7.5                                                                              7.6                                                                               8.5                                                                               7.6                                                                              6.6                                                                              6.4                                                                              6.5                                                                              5.3                                                                              19.8                                                                              18.4                   T.Y. ORIGINAL   10.1                                                                             11.3                                                                             10.8                                                                             11.4                                                                             11.5                                                                             10.7                                                                              11.4                                                                              11.5                                                                             11.3                                                                             11.3                                                                             11.8                                                                             12.5                                                                              12.6                   (NO AGEING)                                                                   0% STRAIN       93 99 105                                                                              100                                                                              99 107 97  99 101                                                                              97 76 94  94                     % ORIGINAL T.Y.                                                               1/2% STRAIN     96 101                                                                              107                                                                              100                                                                              100                                                                              107 86  99 102                                                                              103                                                                               0 95  95                     % ORIGINAL T.Y.                                                               1% STRAIN       105                                                                              100                                                                              107                                                                              101                                                                              101                                                                              106 100 99 102                                                                              102                                                                               0 94  96                     % ORIGINAL T.Y.                                                               2% STRAIN       80 81 105                                                                               99                                                                              98 105 77  98 100                                                                              99  0 94  94                     % ORIGINAL T.Y.                                                               __________________________________________________________________________     *Comparative Examples                                                         **Nylon 6.6 in example Q has been extruded once following the same            extrusion condition used for preparation of PPE/Nylon 6.6 blends before       molding. Nylon 6.6 in example R is the virgin resin.                     

We claim:
 1. A thermoplastic composition comprising(a) a firstpolyphenylene ether resin; (b) a polyamide resin; and (c) acompatibilization agent which is a second polyphenylene ether modifiedwith an acyl functional compound wherein said acyl functional compoundcontains in its molecule both (i) at least one group having the formula##STR15## where X is F, Cl, Br, I, OH, ##STR16## where R is H or analkyl or aryl radical and (ii) at least one carboxylic acid, acidanhydride, acid amide, imido, carboxylic acid ester, amino or hydroxylgroup; wherein groups (i) and (ii) are covalently bonded through adivalent hydrocarbon radical and are not both simultaneously a COOHgroup; and wherein compound (c) is presentin an amount sufficient toeffect compatibilization of resinous components (a) and (b).
 2. Acomposition as in claim 1 wherein the compatibilizing compound (c) isproduced by reaction of polyphenylene ether with a molecule containinggroups (i) and (ii) and the compatibilizing compound (c) containsbetween 0.1 and 6 weight percent of the molecule containing groups (i)and (ii) covalently bonded to polyphenylene ether.
 3. A composition asin claim 1 wherein compatibilizing compound (c) is present in an amountof, approximately, 1 to 95 parts by weight per 100 parts of resinouscomponents (a) and (b).
 4. A composition as in claim 1 wherein resinouscomponents (a) and (b) are comprised of 5 to 95 weight percentpolyphenylene ether and 95 to 5 weight percent polyamide.
 5. Acomposition as in claim 4 wherein said compatibilizing compound (c) isfirst precompounded or prereacted with said polyphenylene ether resin.6. A composition as in claim 1 wherein said first or secondpolyphenylene ether is a homopolymer or copolymer having units with therepeating structural formula: ##STR17## wherein the oxygen ether atom ofone unit is connected to the benzene nucleus of the next joining unit,and n is a positive integer of at least 50, and each Q is,independently, a monovalent substituent selected from a group consistingof hydrogen, halogen, hydrocarbon and hydrocarbonoxy groups free of atertiary alpha-carbon atom, and halohydrocarbon and halohydrocarbonoxygroups free of a tertiary alpha-carbon and having at least 2 carbonatoms between the halogen atom and the phenyl nucleus.
 7. A compositionas in claim 6 wherein said polyphenylene ether is primarilypoly(2,6-dimethyl-1,4,phenylene)ether.
 8. A composition as in claim 1wherein said polyamide is selected from the group consisting ofpolyamide 6; polyamide 6/6; polyamide 4/6; polyamide 12 and polyamide6/10.
 9. A composition as in claim 8 wherein said polyamide is selectedfrom the group consisting of polyamide 6/6, polyamide 6, andcombinations thereof.
 10. A composition as in claim 1 wherein compound(c) is a reaction product of a first compound selected from the groupconsisting of chloroformylsuccinic anhydride, chloroethyanolysuccinicanhydride, trimellitic anhydride acid chloride, trimellitic anhydrideacid acetic anhydride, and terephthalic acid acid chloride, reacted withpolyphenylene ether.
 11. A composition as in claim 1 wherein compound(c) is a reaction of trimellitic anhydride acid chloride andpolyphenylene ether.
 12. A composition as in claim 1 which furthercomprises not more than about 50% by weight based on the totalcomposition of a rubbery high-molecular weight polymer.
 13. Acomposition as in claim 12 wherein the rubbery high-molecular weightpolymer is present in an amount of not more than about 35% by weightbased on the total composition.
 14. A composition as in claim 12 whereinthe rubbery high-molecular weight polymer is a hydrogenated ornon-hydrogenated styrene-butadiene diblock- or triblockcopolymer.
 15. Acomposition as in claim 1 which further comprises not more than about50% by weight based on the total composition of an alkenyl aromaticpolymer.
 16. A composition as in claim 15 wherein the alkenyl aromaticcompound is a styrene homopolymer or copolymer.
 17. A composition as inclaim 16 wherein the alkenyl aromatic compound is a rubber modified highimpact polystyrene.
 18. A composition as in claim 1 wherein thecomposition further comprises a phosphite stabilizer.
 19. A compositionas in claim 1 wherein the composition further comprises a phosphatecompound.
 20. A composition as in claim 1 wherein the compositionfurther comprises a reinforcing amount of an agent selected from thegroup consisting of glass fiber, carbon fiber, and mineral fillers. 21.A composition as in claim 8 wherein said polyamide is modified with animpact strength improving amount of an EPDM-g-MA rubber.